Effect of Additives and Cooling Rates on the Electrical Resistivity of $BaTiO_3$ Ceramics: (II) Multi-Component Systems of $TiO_2$, $SiO_2$ and $Al_2O_3$ Additives

$BaTiO_3$ 세라믹스의 전기저항에 미치는 첨가제와 냉각속도의 영향: (II) $TiO_2$, $SiO_2$$Al_2O_3$ 복합첨가

  • 염희남 (명지대학교 무기재료공학과) ;
  • 하명수 (명지대학교 무기재료공학과) ;
  • 이재춘 (명지대학교 무기재료공학과) ;
  • 정윤중 (명지대학교 무기재료공학과)
  • Published : 1991.10.01

Abstract

Microstructure, room temperature resistivity and temperature coefficient of resistance of BaTiO3 ceramics were characterized and measured in this study. The basic composition of the BaTiO3 cremics was formed by adding 0.25 mol% Dy2O3 and 0.07 mol% MnO2 to the BaTiO3 composition. Samples of the BaTiO3 ceramics were prepared by adding various amounts of the TiO2, SiO2 and Al2O3 to the basic composition. An addition of 1 mol% TiO2, 2 mol% SiO2 and 0.5 mol% Al2O3 to the basic composition resulted both the values of the room temperature resistivity and the temperatured coefficient being maxium. Meanwhile, an addition of 1 mol% TiO2 and 1 mol% Al2O3 to the basic composition resulted the value of the room temperature resistivity maxium and the temperature coefficient minimum. The temperature coefficient showed a maximum value as well as a minimum value when the three kinds of the additives were added together to the basic composition of the BaTiO3 ceramics. Maxed phases of BaTi3O7, BaTiSiO5 and BaAl2Si2O8 were present at the grain boundary.

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References

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